By default, Remote Desktop listens on port 3389. If you want to change this port, there is no easy way to do it in Windows. You might have to tweak with the registry from “HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\TerminalServer\WinStations\RDP-Tcp” (via regedit) in order to change your remote desktop port. Lets say you have different computers using the remote desktop connection but require them to be running on different ports. Or require configuring firewalls for which you will need to know the Remote Desktop port. This may be so because the Remote Desktop port can be used without opening up any extra ports when working on firewalls. RDP Changer is a simple application that allows instantly changing the Remote Desktop port. Just launch RDP Changer, enter a port name and click Change.
You will require rebooting your system for the changes to take effect. The listening port for Remote Desktop can also be changed temporarily by the following method: log in to the remote desktop, type the name or IP of the remote computer, add a colon and the desired port (for example, Computer1:3390). However, for additional security, firewall configuration and other purposes, the default port can be changed with the help of RDP Changer. You can revert to 3389 again either by manually entering it or choosing the Default option in RDP Changer.
It works on Windows XP, Windows Vista, Windows 7, Windows Server 2003 and Windows Server 2008.
Download RDP Changer